diff --git a/pkg/instrumentation/flags.go b/pkg/instrumentation/flags.go
index 43a7ac6f6..22273b683 100644
--- a/pkg/instrumentation/flags.go
+++ b/pkg/instrumentation/flags.go
@@ -47,9 +47,9 @@ const (
 	// defaultJaegerAgent is the default Jaeger agent endpoint.
 	defaultJaegerAgent = ""
 	// defaultHTTPEndpoint is the default HTTP endpoint serving Prometheus /metrics.
-	defaultHTTPEndpoint = ":8888"
+	defaultHTTPEndpoint = ""
 	// defaultPrometheusExport is the default state for Prometheus exporting.
-	defaultPrometheusExport = "true"
+	defaultPrometheusExport = "false"
 )
 
 // options encapsulates our configurable instrumentation parameters.
diff --git a/pkg/instrumentation/instrumentation_test.go b/pkg/instrumentation/instrumentation_test.go
index 2a2141fa9..9c4685097 100644
--- a/pkg/instrumentation/instrumentation_test.go
+++ b/pkg/instrumentation/instrumentation_test.go
@@ -18,6 +18,7 @@ import (
 	"flag"
 	"io/ioutil"
 	"net/http"
+	"strings"
 	"testing"
 )
 
@@ -42,22 +43,31 @@ func TestSamplingIdempotency(t *testing.T) {
 func TestPrometheusConfiguration(t *testing.T) {
 	flag.Set("logger-debug", "all")
 
+	if opt.HTTPEndpoint == "" {
+		opt.HTTPEndpoint = ":0"
+	}
+
 	s := newService()
 	s.Start()
 
-	checkPrometheus(t, opt.HTTPEndpoint, !opt.PrometheusExport)
+	address := s.http.GetAddress()
+	if strings.HasSuffix(opt.HTTPEndpoint, ":0") {
+		opt.HTTPEndpoint = address
+	}
+
+	checkPrometheus(t, address, !opt.PrometheusExport)
 
 	opt.PrometheusExport = !opt.PrometheusExport
 	s.reconfigure()
-	checkPrometheus(t, opt.HTTPEndpoint, !opt.PrometheusExport)
+	checkPrometheus(t, address, !opt.PrometheusExport)
 
 	opt.PrometheusExport = !opt.PrometheusExport
 	s.reconfigure()
-	checkPrometheus(t, opt.HTTPEndpoint, !opt.PrometheusExport)
+	checkPrometheus(t, address, !opt.PrometheusExport)
 
 	opt.PrometheusExport = !opt.PrometheusExport
 	s.reconfigure()
-	checkPrometheus(t, opt.HTTPEndpoint, !opt.PrometheusExport)
+	checkPrometheus(t, address, !opt.PrometheusExport)
 
 	s.http.Shutdown(true)
 	s.Stop()